Spectral domain optical coherence tomography method and system for real-time feedback adjustment

Abstract

The invention relates to the technical field of optical imaging, in particular to a spectral domain optical coherence tomography method and system with real-time feedback adjustment. The method comprises the steps that emergent light of a broadband light source is modulated into a space-time wave packet through the space-time wave packet technology, and then a first broadband light beam is generated; generating a second broadband light beam from the first broadband light beam after generating wave packets of different wavelengths in spatial continuous distribution; the deflection angle of the second broadband light beam is adjusted, sample reflected light consistent with the wavelength of the second broadband light beam is returned, and the propagation speed of the space-time wave packet in the medium with the variable refractive index is consistent, so that the operation condition of spectral domain optical coherence tomography is fed back and adjusted in real time. And the light source wavelength, the wave packet wavelength, the focusing position and the scanning position of spectral domain optical coherence tomography are fed back and adjusted, so that sample position information or image information is provided with high imaging precision, high speed and high output.

Description

Technical Field

[0001] The present invention relates to the field of optical imaging technology. Specifically, it relates to a spectral domain optical coherence tomography method and system with real-time feedback adjustment. Background Art

[0002] Currently, during the optical processing, due to the dispersion of optical components, the imaging accuracy will be affected. Adjusting the optical components during use will affect the imaging speed and cannot provide the sample position information or image information in real time.

[0003] Traditional dispersion compensation methods are divided into hardware compensation and software compensation. The hardware compensation method usually adds optical elements with specific refractive indices in the reference arm to achieve dispersion compensation. The software compensation compensates the measurement results by designing specific algorithms. Both of these methods increase the complexity of the imaging system, raise the usage cost, and there are also large systematic errors and subjective errors in the dispersion of the imaging system. During use, it is also necessary to adjust the optical elements in a timely manner.

[0004] The spatio-temporal wavepacket beam is a pulsed beam with an exact correlation between the spatial and temporal degrees of freedom. In such a beam, different spatial frequency components vary according to different temporal frequencies, that is, each angle in the wave is associated with a specific wavelength. It can effectively introduce a controllable correlation between spatial and temporal frequencies, generate wavepackets with different wavelengths distributed continuously in space from a broadband beam, and allocate the light at each angle in the wave to different wavelengths. It can achieve transmission at the interface of two materials without changing its speed.

[0005] Therefore, it is necessary to provide a method that can provide the sample position information or image information with high imaging accuracy, high speed, and high output while having a consistent propagation speed in a medium with continuously changing refractive index, so as to adjust the operation of the spectral domain optical coherence tomography system in real-time feedback. Summary of the Invention

[0006] An embodiment of the present invention provides a spectral domain optical coherence tomography method and system with real-time feedback adjustment to adjust the operation of spectral domain optical coherence tomography in real-time feedback.

[0007] According to an embodiment of the present invention, a spectral domain optical coherence tomography method with real-time feedback adjustment is provided, including the following steps: Modulate the emitted light of the broadband light source into a spatio-temporal wavepacket by the spatio-temporal wavepacket technology to generate a first broadband beam; Generate a second broadband beam after generating wavepackets with different wavelengths distributed continuously in space from the first broadband beam; Adjust the deflection angle of the second broadband beam and return the sample reflected light consistent with the wavelength of the second broadband beam. The spatio-temporal wave packets propagate at a consistent speed in the medium with refractive index changes to provide real-time feedback for adjusting the operation of spectral domain optical coherence tomography.

[0008] Furthermore, in combination with the wavelength scanning mode of spectral domain optical coherence tomography, feedback is used to adjust the light source wavelength, wave packet wavelength, focusing position, and scanning position of spectral domain optical coherence tomography.

[0009] According to another embodiment of the present invention, a spectral domain optical coherence tomography system with real-time feedback adjustment is provided, including: A broadband light source, connected to a control unit, for generating a first broadband beam; A spatio-temporal wave packet unit, arranged at the light output port of the broadband light source. After the first broadband beam generates wave packets with different wavelengths distributed continuously in space, a second broadband beam is generated. A part of the second broadband beam is transmitted to the image beam unit, reference beam unit, and interferometer, and the deflection angle of another part of the second broadband beam is adjusted, and the sample reflected light consistent with the wavelength of the other part of the second broadband beam is transmitted to the spatio-temporal wave packet unit; An image beam unit, connected to the interferometer. A part of the second broadband beam regenerated by the spatio-temporal wave packet unit is divided by the interferometer into a first image beam and a first reference beam. The image beam unit transmits the first image beam to the sample and returns the second image beam reflected by the sample to the interferometer; A reference beam unit, guiding the first reference beam to a reference mirror and having a second reference beam orthogonal to the wavelength of the reference mirror returned to the interferometer; An interferometer, connected to the broadband light source, image beam unit, reference beam unit, and image processing and display unit, for interfering the returned second image beam and the returned second reference beam to generate interference light; A galvanometer scanning unit, connected in the output optical path of the broadband light source, for adjusting the position of another part of the second broadband beam and simultaneously recording the position and orientation information of the scanning points by scanning the sample from the surface to different depths, widths, and axial positions in real time.

[0010] Furthermore, the system further includes: A high-speed camera, connected to the image beam unit and connected to the image processing and display unit through an electrical transmission unit, for taking a sample photo of the scanning point and transmitting it to the image processing and display unit; An image processing and display unit, connected to the interferometer and connected to the galvanometer scanning unit, high-speed camera, and control unit through an electrical transmission unit, for analyzing the sample photo of the scanning point taken by the high-speed camera, the interference light signal, and the position and orientation information of the scanning point, generating a real-time image, and displaying the determined result; A control unit, which is connected to an image processing and display unit, a spatio-temporal wave packet unit, and a broadband light source. According to the real-time position, orientation, and three-dimensional image information of the sample determined by the image processing and display unit, it adjusts in real-time and feedback the wavelength of the third broadband light beam emitted by the broadband light source, adjusts in real-time and feedback the wave packet wavelength of the spatio-temporal wave packet unit and generates a fourth broadband light beam, adjusts in real-time and feedback the deflection angle of the fourth broadband light beam, adjusts in real-time and feedback the focusing position of the image beam unit and the high-speed camera, and adjusts the scanning position of the laser galvanometer scanning unit for imaging.

[0011] Furthermore, the spatio-temporal wave packet unit includes a first grating, a cylindrical lens, a spatial light modulator, a second grating, an electro-optic semi-transparent and semi-reflective mirror, an electro-optic semi-transparent and semi-reflective mirror driver, a deflection angle encoder, and a deflection angle encoder driver that are sequentially connected through an optical fiber transmission unit; The first grating is a transmissive grating with a gradually changing surface curvature, which separates the first broadband light into lights with different wavelengths that are continuously distributed in space; The cylindrical lens is a cylindrical lens with a gradually changing surface curvature, which converts the lights with different wavelengths that are continuously distributed in space into parallel lights; The spatial light modulator performs phase modulation on the parallel light incident on the cylindrical lens and focuses it on the second grating; The second grating is a transmissive grating with a gradually changing surface curvature, which generates and stably outputs a second broadband light beam from the phase-modulated parallel light; The deflection angle encoder is connected to the electro-optic semi-transparent and semi-reflective mirror and the deflection angle encoder driver through an electrical transmission unit, and collects and measures the deflection angle of the electro-optic semi-transparent and semi-reflective mirror; The deflection angle encoder driver is connected to the deflection angle encoder and the control unit through an electrical transmission unit, drives the deflection angle encoder to collect and measure the deflection angle of the electro-optic semi-transparent and semi-reflective mirror, and transmits the deflection angle to the control unit; The electro-optic semi-transparent and semi-reflective mirror driver is connected to the electro-optic semi-transparent and semi-reflective mirror and the control unit through an electrical transmission unit, and drives the rotation of the electro-optic semi-transparent and semi-reflective mirror at the deflection angle collected by the deflection angle encoder under the control of the control unit; the electro-optic semi-transparent and semi-reflective mirror transmits another part of the second broadband light beam to the sample at the deflection angle collected by the deflection angle encoder and reflects the sample reflected light with the same wavelength as another part of the second broadband light beam back to the spatio-temporal wave packet unit.

[0012] Furthermore, the transmittance of the second grating is greater than that of the first grating. The first grating and the second grating form an optical separation and regeneration system, which is used to compensate for the optical attenuation caused by the long-distance transmission of another part of the second broadband light beam; The surface curvature of the second grating is greater than that of the first grating, which is used to generate spatio-temporal wave packets with different wavelengths in a spatially continuous distribution from the first broadband beam generated by a broadband light source, and then generate a stable second broadband beam and transmit it. The stable second broadband beam is processed by the spatio-temporal wave packet unit and propagates at a constant speed in media with different refractive indices without being affected by dispersion.

[0013] Furthermore, the electro-optic semi-transparent semi-reflective mirror, the electro-optic semi-transparent semi-reflective mirror driver, the deflection angle encoder, and the deflection angle encoder driver adjust the deflection angle of another part of the second broadband beam under the control of the control unit and transmit the sample reflected light with the same wavelength as another part of the second broadband beam to the spatio-temporal wave packet unit, the image beam unit, the interferometer, and the high-speed camera. Real-time feedback adjustment of the deflection angle of the second broadband beam can continuously select a monochromatic light, achieving an imaging resolution consistent with the spectral resolution of the light source.

[0014] Furthermore, the image beam unit includes an electro-optic semi-transparent semi-reflective mirror, a collimating and beam-expanding device, a third grating, and a focusing lens connected in sequence through a fiber optic transmission unit; The electro-optic semi-transparent semi-reflective mirror combines the optical path of the high-speed camera into the main optical path and transmits the sample reflected light with the same wavelength as a part of the second broadband beam reflected by the sample to the interferometer and the high-speed camera; The collimating and beam-expanding device is used to expand the diameter of a part of the second broadband beam and collimate a part of the second broadband beam; The third grating is a diffraction grating, which is used to reduce the influence of sample scattering on the imaging of the image beam unit; The focusing lens is a scanning lens, which is arranged in the output optical path of the imaging of the image beam unit and is used to focus a part of the second broadband beam adjusted in position by the laser galvanometer scanning unit on the sample.

[0015] Furthermore, the reference beam unit includes a diaphragm, a lens, and a reference mirror connected in sequence through a fiber optic transmission unit; The diaphragm is a field diaphragm, which is used to obtain a circular light spot in the first reference beam; The lens is a cylindrical lens, which is used to transmit the first reference beam adjusted by the diaphragm; The reference mirror is a multi-faceted reflecting mirror, which guides the first reference beam to the reference mirror and has a second reference beam orthogonal to the wavelength of the reference mirror returning to the interferometer.

[0016] Furthermore, the optical paths of the three-dimensional laser galvanometer scanning unit, the image beam unit, and the high-speed camera are coaxial, and the sample is simultaneously within the scanning range of the three-dimensional laser galvanometer scanning unit, the imaging range of the image beam unit, and the shooting range of the high-speed camera; The focusing lens is fixed directly above the sample vertically and is used to focus the second broadband beam on the sample. At the same time, it serves as the imaging lens of the image beam unit, the scanning lens of the three-dimensional laser galvanometer scanning unit, and the shooting lens of the high-speed camera.

[0017] A storage medium stores a program file capable of implementing the spectral domain optical coherence tomography method with real-time feedback adjustment as described in any one of the above.

[0018] A processor is used to run a program. When the program runs, it executes the spectral domain optical coherence tomography method with real-time feedback adjustment as described in any one of the above.

[0019] In the spectral domain optical coherence tomography method and system with real-time feedback adjustment in the embodiments of the present invention, the emitted light of a broadband light source is modulated into a spatio-temporal wave packet by the spatio-temporal wave packet technology to generate a first broadband light beam. After generating wave packets with different wavelengths that are continuously distributed in space from the first broadband light beam, a second broadband light beam is generated. The deflection angle of the second broadband light beam is adjusted, and the sample reflected light with the same wavelength as the second broadband light beam is returned to the system. The spatio-temporal wave packet propagates at a consistent speed in a medium with refractive index changes and is free of dispersion, improving the imaging accuracy of the spectral domain optical coherence tomography system. Combining with the wavelength scanning mode of the spectral domain optical coherence tomography system, the light source wavelength, wave packet wavelength, focusing position, and scanning position of the spectral domain optical coherence tomography system are feedback-adjusted, achieving high imaging accuracy, high speed, and high output to provide sample position information or image information, and real-time feedback-adjusting the operation of the spectral domain optical coherence tomography system. Description of the Drawings

[0020] The drawings described herein are used to provide a further understanding of the present invention, and constitute a part of this application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings: Figure 1 is a schematic structural diagram of a spectral domain optical coherence tomography system with intraoperative real-time adjustment provided by an embodiment of the present invention.

[0021] Description of the Reference Numerals in the Drawings 1 - broadband light source; 2 - spatio-temporal wave packet unit; 21 - first grating; 22 - cylindrical lens; 23 - spatial light modulator; 24 - second grating; 25 - electric semi-transparent semi-reflective mirror; 26 - electric semi-transparent semi-reflective mirror driver; 27 - deflection angle encoder; 28 - deflection angle encoder driver; 3 - image beam unit; 32 - collimating and beam expanding device; 33 - third grating; 34 - focusing lens; 4 - reference beam unit; 41 - aperture; 42 - lens; 43 - reference mirror; 5 - interferometer; 6 - image processing and display unit; 7 - galvanometer scanning unit; 8 - high-speed camera; 9 - control unit; 10 - optical fiber transmission unit; 11 - electrical transmission unit. Detailed Embodiments

[0022] To enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0023] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above accompanying drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0024] A spectral domain optical coherence tomography system and method with real-time feedback adjustment provided by the present invention modulate the emitted light of a broadband light source into a spatio-temporal wave packet through spatio-temporal wave packet technology to generate a first broadband beam, generate wave packets of different wavelengths with spatially continuous distribution from the first broadband beam and then generate a second broadband beam, adjust the deflection angle of the second broadband beam and return the sample reflected light with the same wavelength as the second broadband beam to the system. The spatio-temporal wave packet propagates at a consistent speed in a medium with refractive index change and has no dispersion, improving the imaging accuracy of the spectral domain optical coherence tomography system. Combining with the wavelength scanning mode of the spectral domain optical coherence tomography system, it feedback-adjusts the light source wavelength, wave packet wavelength, focusing position and scanning position of the spectral domain optical coherence tomography system, realizes providing sample position information or image information with high imaging accuracy, high speed and high output, and real-time feedback-adjusts the operation of the spectral domain optical coherence tomography system.

[0025] To achieve the above object, the solution provided by the present invention is: Please refer to Figure 1, a spectral domain optical coherence tomography system with feedback adjustment provided by the present invention modulates the emitted light of a broadband light source into a spatio-temporal wave packet through spatio-temporal wave packet technology and then generates a broadband light beam. The spatio-temporal wave packet propagates at a consistent speed in a medium with a refractive index change and has no dispersion in the imaging system, improving the imaging accuracy of the spectral domain optical coherence tomography system. Combining with the wavelength scanning mode of the spectral domain optical coherence tomography system, it feedback-adjusts the light source wavelength, wave packet wavelength, focusing position, and scanning position of the spectral domain optical coherence tomography system, realizing the provision of tissue position information or image information with high imaging accuracy, high speed, and high output, and expanding the application range of the spectral domain optical coherence tomography system.

[0026] A spectral domain optical coherence tomography system with feedback adjustment includes a broadband light source 1, a spatio-temporal wave packet unit 2, an image beam unit 3, a reference beam unit 4, an interferometer 5, a galvanometer scanning unit 7, an image processing and display unit 6, a high-speed camera 8, a control unit 9, an optical fiber transmission unit 10, and an electrical transmission unit 11, where: The broadband light source 1, the broadband light source 1 is connected to the control unit 9 through the electrical transmission unit 11 and is used to generate a first broadband light beam; The spatio-temporal wave packet unit 2, the spatio-temporal wave packet unit 2 is arranged at the light output port of the broadband light source 1. The first broadband light beam generates wave packets with different wavelengths distributed continuously in space and then generates a second broadband light beam. A part of the second broadband light beam is transmitted to the image beam unit 3, the reference beam unit 4, and the interferometer 5, and the deflection angle of another part of the second broadband light beam is adjusted and the sample reflected light with the same wavelength as another part of the second broadband light beam is transmitted to the spatio-temporal wave packet unit 2; The image beam unit 3, the image beam unit 3 is connected to the interferometer 5 through the optical fiber transmission unit 10. A part of the second broadband light beam regenerated by the spatio-temporal wave packet unit passes through the interferometer 5 and is divided into a first image beam and a first reference beam. The image beam unit 3 transmits the first image beam to the sample and returns the second image beam reflected by the sample to the interferometer 5; The reference beam unit 4, the reference beam unit 4 guides the first reference beam to the reference mirror 43 and has a second reference beam orthogonal to the wavelength of the reference mirror 43 return to the interferometer 5; The interferometer 5, the interferometer 5 is connected to the broadband light source 1, the image beam unit 3, the reference beam unit 4, and the image processing and display unit 6 through the optical fiber transmission unit 10, interferes the returned second image beam and the returned second reference beam to generate interference light, and transmits the interference light to the image processing and display unit 6; The galvanometer scanning unit 7, the galvanometer scanning unit 7 is connected in the output optical path of the broadband light source 1 through the optical fiber transmission unit 10 and is used to adjust the position of another part of the second broadband light beam, and simultaneously scan the sample from the surface to different depths, widths, and axial positions inside, and record the position and orientation information of the scanning points and transmit them to the image processing and display unit 6; A high-speed camera 8, which is connected to an image bundle unit 3 through an optical fiber transmission unit 10 and connected to an image processing and display unit 6 through an electrical transmission unit 11, takes a sample photo of a scanning point and transmits it to the image processing and display unit 6; An image processing and display unit 6, which is connected to an interferometer 5 through an optical fiber transmission unit 10 and connected to a laser galvanometer scanning unit 7, a high-speed camera 8 and a control unit 9 through an electrical transmission unit 11, analyzes the sample photo of the scanning point taken by the high-speed camera 8, the interference light signal, and the position and orientation information of the scanning point, generates a real-time image and displays the determined result; A control unit 9, which is connected to the image processing and display unit 6, a space-time wave packet unit 2 and a broadband light source 1 through an electrical transmission unit 11, adjusts the wavelength of the third broadband light beam emitted by the broadband light source 1 in real-time feedback according to the real-time position, orientation and three-dimensional image information of the sample determined by the image processing and display unit 6, adjusts the wave packet wavelength of the space-time wave packet unit 2 in feedback and generates a fourth broadband light beam, adjusts the deflection angle of the fourth broadband light beam in feedback, adjusts the focusing position of the image bundle unit 3 and the high-speed camera 8 and the scanning position of the laser galvanometer scanning unit 7 in feedback for imaging.

[0027] In an embodiment of the present invention, the spatio-temporal wave packet unit 2 includes a first grating 21, a cylindrical lens 22, a spatial light modulator 23, a second grating 24, an electro-optic semi-transmissive semi-reflective mirror 25, an electro-optic semi-transmissive semi-reflective mirror driver 26, a deflection angle encoder 27, and a deflection angle encoder driver 28 that are sequentially connected through an optical fiber transmission unit 10. The first grating 21 is a transmissive grating with a gradually changing surface curvature, which separates the first broadband light into lights of different wavelengths with spatially continuous distribution; the cylindrical lens 22 is a cylindrical lens with a gradually changing surface curvature, which converts the lights of different wavelengths with spatially continuous distribution into parallel lights; the spatial light modulator 23 performs phase modulation on the parallel lights incident on the cylindrical lens 22 and focuses them on the second grating 24; the second grating 24 is a transmissive grating with a gradually changing surface curvature, which generates a second broadband light beam after phase modulation and outputs it stably; the deflection angle encoder 27 is connected to the electro-optic semi-transmissive semi-reflective mirror 25 and the deflection angle encoder driver 28 through an electrical transmission unit 11, and collects and measures the deflection angle of the electro-optic semi-transmissive semi-reflective mirror 25; the deflection angle encoder driver 28 is connected to the deflection angle encoder 27 and the control unit 9 through an electrical transmission unit 11, drives the deflection angle encoder 27 to collect and measure the deflection angle of the electro-optic semi-transmissive semi-reflective mirror 25, and transmits the deflection angle to the control unit 9; the electro-optic semi-transmissive semi-reflective mirror driver 26 is connected to the electro-optic semi-transmissive semi-reflective mirror 25 and the control unit 9 through an electrical transmission unit 11, and drives the rotation of the electro-optic semi-transmissive semi-reflective mirror 25 at the deflection angle collected by the deflection angle encoder 27 under the control of the control unit 9; the electro-optic semi-transmissive semi-reflective mirror 25 transmits another part of the second broadband light beam to the sample at the deflection angle collected by the deflection angle encoder 27 and reflects the sample reflected light with the same wavelength as another part of the second broadband light beam back to the spatio-temporal wave packet unit 2.

[0028] Among them, the transmittance of the second grating 24 is greater than that of the first grating 21. The first grating 21 and the second grating 24 form an optical separation and regeneration system, which is used to compensate for the optical attenuation caused by the long-distance transmission of another part of the second broadband light beam and improve the quality of optical transmission.

[0029] Among them, the surface curvature of the second grating 24 is greater than that of the first grating 21, which is used to generate spatio-temporal wave packets of different wavelengths with spatially continuous distribution from the first broadband light beam generated by the broadband light source 1, and then generate a stable second broadband light beam and transmit it. The stable second broadband light beam is processed by the spatio-temporal wave packet unit 2 and has an unchanged propagation speed and is not affected by dispersion in media with different refractive indices.

[0030] Among them, the first broadband light beam of the broadband light source 1 is modulated into spatio-temporal wave packets of different wavelengths with spatially continuous distribution. The spatio-temporal wave packets of different wavelengths with spatially continuous distribution have the same propagation speed in a medium with a changing refractive index, and there is no dispersion in the optical system, so there is no need to add additional dispersion compensation hardware and complex software processing, which improves the imaging accuracy of the imaging system.

[0031] Among them, the electrically controlled semi-transparent semi-reflective mirror 25, the electrically controlled semi-transparent semi-reflective mirror driver 26, the deflection angle encoder 27, and the deflection angle encoder driver 28 adjust the deflection angle of the other part of the second broadband light beam under the control of the control unit 9 and transmit the sample reflected light with the same wavelength as the other part of the second broadband light beam to the spatio-temporal wave packet unit 2, the image beam unit 3, the interferometer 5, and the high-speed camera 8. The real-time feedback adjustment of the deflection angle of the second broadband light beam can continuously select the monochromatic light accurately, achieving an imaging resolution consistent with the spectral resolution of the broadband light source 1.

[0032] In an embodiment of the present invention, the image beam unit 3 includes an electrically controlled semi-transparent semi-reflective mirror 25, a collimating and beam expanding device 32, a third grating 33, and a focusing lens 34 that are sequentially connected through the optical fiber transmission unit 10. The electrically controlled semi-transparent semi-reflective mirror 25 combines the optical path of the high-speed camera 8 into the main optical path and transmits the sample reflected light with the same wavelength as a part of the second broadband light beam reflected by the sample to the interferometer 5 and the high-speed camera 8; the collimating and beam expanding device 32 is used to expand the diameter of a part of the second broadband light beam and collimate a part of the second broadband light beam; the third grating 33 is a diffraction grating, which is used to reduce the influence of sample scattering on the imaging of the image beam unit 3; the focusing lens 34 is a scanning lens, which is arranged in the output optical path of the imaging of the image beam unit 3 and is used to focus a part of the second broadband light beam whose position has been adjusted by the laser galvanometer scanning unit 7 on the sample.

[0033] Among them, the collimating and beam expanding device 32 expands the diameter of a part of the second broadband light beam, thereby reducing the divergence angle of a part of the second broadband light beam and improving the focusing quality of a part of the second broadband light beam.

[0034] Among them, the third grating 33 reduces the influence of sample scattering on the imaging of the image beam unit 3 and improves the imaging accuracy of the imaging system.

[0035] In an embodiment of the present invention, the reference beam unit 4 includes a field stop 41, a lens 42, and a reference mirror 43 that are sequentially connected through the optical fiber transmission unit 10. The field stop 41 is a field stop and is used to obtain a circular light spot in the first reference beam; the lens 42 is a cylindrical lens and is used to transmit the first reference beam adjusted by the field stop; the reference mirror 43 is a multi-faceted reflecting mirror, which guides the first reference beam to the reference mirror 43 and has a second reference beam orthogonal to the wavelength of the reference mirror 43 return to the interferometer 5.

[0036] Among them, the field stop 41 obtains a circular light spot in the first reference beam, making the light spot radially uniformly distributed after the first reference beam is focused, reducing the diameter of the focused light spot, and improving the focusing quality of the light spot.

[0037] In an embodiment of the present invention, the optical paths of the three-dimensional galvanometer scanning unit 7, the image beam unit 3, and the high-speed camera 8 are coaxial, and the sample is simultaneously within the scanning range of the three-dimensional galvanometer scanning unit 7, the imaging range of the image beam unit 3, and the shooting range of the high-speed camera 8.

[0038] In an embodiment of the present invention, the focusing lens 34 is fixed directly above the sample vertically, and is used to focus the second broadband beam onto the sample, and at the same time serves as the imaging lens of the image beam unit 3, the scanning lens of the three-dimensional galvanometer scanning unit 7, and the shooting lens of the high-speed camera 8.

[0039] On the other hand, the present invention also provides a working method for the frequency-domain optical coherence tomography imaging system with real-time adjustment, which is as follows: The broadband light source 1 generates a first broadband beam and transmits it to the spatio-temporal wave packet unit 2. The first grating 21 separates the first broadband light into lights with different wavelengths continuously distributed in space, and converts them into parallel light through the cylindrical lens 22. The parallel light is phase-modulated in the spatial light modulator 23 and focused on the second grating 24 to generate a second broadband beam and stably output it. The deflection angle encoder 27 collects and measures the deflection angle of the electro-optic semi-transmissive semi-reflective mirror 25 under the drive of the deflection angle encoder driver 28, and transmits the deflection angle to the control unit 9. The electro-optic semi-transmissive semi-reflective mirror 25 transmits another part of the second broadband beam to the sample at the deflection angle collected by the deflection angle encoder 27 under the control of the control unit 9, and reflects the sample reflected light with the same wavelength as another part of the second broadband beam back to the spatio-temporal wave packet unit 2; The interferometer 5 divides a part of the second broadband beam regenerated by the spatio-temporal wave packet unit 2 into a first image beam and a first reference beam. The first image beam passes through the image beam unit 3 and is focused on the sample, and transmits the reflected light of the sample with the same wavelength as a part of the second broadband beam back to the interferometer 5 and the high-speed camera 8; The first reference beam unit guides the reference beam to the reference mirror 43 and has a second reference beam orthogonal to the wavelength of the reference mirror 43 return to the interferometer 5; The returned second image beam and the returned second reference beam interfere at the interferometer 5 to generate interference light and transmit it to the image processing and display unit 6; The galvanometer scanning unit 7 adjusts the position of a part of the second broadband beam, and scans the sample from the surface to different depths, widths, and axial positions in real time, and simultaneously records the position and orientation information of the scanning points and transmits them to the image processing and display unit 6; The high-speed camera 8 takes pictures of the sample at the scanning points recorded by the three-dimensional galvanometer scanning unit 7 and transmits them to the image processing and display unit 6; The image processing and display unit 6 analyzes the sample pictures of the scanning points taken by the high-speed camera 8, the interference light, and the position and orientation information of the scanning points, generates a real-time image and displays the determined result; Based on the synchronized real-time position, orientation, and three-dimensional image information of the sample determined by the image processing and display unit 6, the control unit 9 adjusts in real-time feedback the wavelength of the third broadband light beam emitted by the broadband light source 1, adjusts in real-time feedback the wave packet wavelength of the spatio-temporal wave packet unit 2 and generates a fourth broadband light beam, adjusts in real-time feedback the deflection angle of the fourth broadband light beam, adjusts in real-time feedback the focusing positions of the image beam unit 3 and the high-speed camera 8, and adjusts the scanning position of the galvanometric scanner unit 7 for imaging.

[0040] The spectral domain optical coherence tomography system and method with real-time feedback adjustment provided in the above embodiments of the present application can be used for imaging industrial samples to achieve sample detection, and can also be applied to imaging of human or animal tissues, with wide applications. A storage medium stores a program file capable of implementing the spectral domain optical coherence tomography method with real-time feedback adjustment as described in any one of the above.

[0041] A processor is used to run a program, wherein when the program runs, it executes the spectral domain optical coherence tomography method with real-time feedback adjustment as described in any one of the above.

[0042] The serial numbers of the above embodiments of the present invention are only for description and do not represent the superiority or inferiority of the embodiments.

[0043] In the above embodiments of the present invention, the descriptions of the various embodiments have their own emphases. For parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0044] In the several embodiments provided by the present application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the system embodiments described above are only illustrative. For example, the division of units can be a logical function division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces. The indirect couplings or communication connections of units or modules can be in electrical or other forms.

[0045] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0046] In addition, in each embodiment of the present invention, each functional unit can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0047] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in each embodiment of the present invention. The foregoing storage medium includes: various media such as USB flash drives, read-only memories (ROMs), random access memories (RAMs), mobile hard disks, magnetic disks, or optical discs that can store program codes.

[0048] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A spectral domain optical coherence tomography method with real-time feedback adjustment, characterized in that, Including the following steps: Modulating the output light of a broadband light source into a spatio-temporal wave packet by spatio-temporal wave packet technology to generate a first broadband light beam; Generating a second broadband light beam after generating wave packets with different wavelengths that are spatially continuously distributed from the first broadband light beam; Adjusting the deflection angle of the second broadband light beam and returning the sample reflected light with the same wavelength as the second broadband light beam. The spatio-temporal wave packets have the same propagation speed in the medium with refractive index change to adjust the operation of spectral domain optical coherence tomography in real time.

2. The spectral domain optical coherence tomography method with real-time feedback adjustment according to claim 1, wherein Combining with the wavelength scanning mode of spectral domain optical coherence tomography, feedback-adjusting the light source wavelength, wave packet wavelength, focusing position and scanning position of spectral domain optical coherence tomography.

3. A spectral domain optical coherence tomography system with real-time feedback adjustment, characterized in that, Including: A broadband light source, which is connected to a control unit and is used to generate a first broadband light beam; A spatio-temporal wave packet unit, which is arranged at the light output port of the broadband light source. After the first broadband light beam generates wave packets with different wavelengths that are spatially continuously distributed, a second broadband light beam is generated. A part of the second broadband light beam is transmitted to an image beam unit, a reference beam unit and an interferometer, and the deflection angle of another part of the second broadband light beam is adjusted and the sample reflected light with the same wavelength as the other part of the second broadband light beam is transmitted to the spatio-temporal wave packet unit; An image beam unit, which is connected to the interferometer. A part of the second broadband light beam regenerated by the spatio-temporal wave packet unit is divided into a first image beam and a first reference beam by the interferometer. The image beam unit transmits the first image beam to the sample and returns the second image beam reflected by the sample to the interferometer; A reference beam unit, which guides the first reference beam to a reference mirror and has a second reference beam orthogonal to the wavelength of the reference mirror returned to the interferometer; An interferometer, which is connected to the broadband light source, the image beam unit, the reference beam unit and an image processing and display unit, and interferes the returned second image beam and the returned second reference beam to generate interference light; A galvanometer scanning unit, which is connected in the output optical path of the broadband light source and is used to adjust the position of another part of the second broadband light beam, and simultaneously record the position and orientation information of the scanning points while scanning the sample from the surface to different depths, widths and axial positions inside; 4. The spectral domain optical coherence tomography system with real-time feedback adjustment according to claim 3, wherein The system further includes: A high-speed camera, which is connected to the image beam unit and is connected to the image processing and display unit through an electrical transmission unit, takes a sample photo of the scanning point and transmits it to the image processing and display unit; An image processing and display unit, which is connected to the interferometer and is connected to the galvanometer scanning unit, the high-speed camera and the control unit through an electrical transmission unit, analyzes the sample photo of the scanning point taken by the high-speed camera, the interference light signal and the position and orientation information of the scanning point, generates a real-time image and displays the determined result; The control unit is connected to the image processing and display unit, the spatio-temporal wave packet unit, and the broadband light source. According to the real-time position, orientation, and three-dimensional image information of the sample determined by the image processing and display unit, it adjusts the wavelength of the third broadband light beam emitted by the broadband light source in real-time feedback, adjusts the wave packet wavelength of the spatio-temporal wave packet unit and generates a fourth broadband light beam, adjusts the deflection angle of the fourth broadband light beam in real-time feedback, adjusts the focusing positions of the image beam unit and the high-speed camera, and adjusts the scanning position of the laser galvanometer scanning unit for imaging.

5. The spectral domain optical coherence tomography system with real-time feedback adjustment according to claim 4, wherein The spatio-temporal wave packet unit includes a first grating, a cylindrical lens, a spatial light modulator, a second grating, an electro-optical semi-transparent and semi-reflective mirror, an electro-optical semi-transparent and semi-reflective mirror driver, a deflection angle encoder, and a deflection angle encoder driver, which are sequentially connected through an optical fiber transmission unit; The first grating is a transmission grating with a gradually changing surface curvature, which separates the first broadband light into lights with different wavelengths continuously distributed in space; The cylindrical lens is a cylindrical lens with a gradually changing surface curvature, which converts the lights with different wavelengths continuously distributed in space into parallel lights; The spatial light modulator performs phase modulation on the parallel light incident on the cylindrical lens and focuses it on the second grating; The second grating is a transmission grating with a gradually changing surface curvature, which generates and stably outputs a second broadband light beam from the phase-modulated parallel light; The deflection angle encoder is connected to the electro-optical semi-transparent and semi-reflective mirror and the deflection angle encoder driver through an electrical transmission unit, and collects and measures the deflection angle of the electro-optical semi-transparent and semi-reflective mirror; The deflection angle encoder driver is connected to the deflection angle encoder and the control unit through an electrical transmission unit, drives the deflection angle encoder to collect and measure the deflection angle of the electro-optical semi-transparent and semi-reflective mirror, and transmits the deflection angle to the control unit; The electro-optical semi-transparent and semi-reflective mirror driver is connected to the electro-optical semi-transparent and semi-reflective mirror and the control unit through an electrical transmission unit, and drives the rotation of the electro-optical semi-transparent and semi-reflective mirror at the deflection angle collected by the deflection angle encoder under the control of the control unit; the electro-optical semi-transparent and semi-reflective mirror transmits another part of the second broadband light beam to the sample at the deflection angle collected by the deflection angle encoder and reflects the sample reflected light with the same wavelength as another part of the second broadband light beam back to the spatio-temporal wave packet unit.

6. The spectral domain optical coherence tomography system with real-time feedback adjustment according to claim 5, wherein The transmittance of the second grating is greater than that of the first grating. The first grating and the second grating form an optical separation and regeneration system, which is used to compensate for the optical attenuation caused by the long-distance transmission of another part of the second broadband light beam; The surface curvature of the second grating is greater than that of the first grating, which is used to generate spatio-temporal wave packets with different wavelengths continuously distributed in space from the first broadband light beam generated by the broadband light source, and then generate and transmit a stable second broadband light beam. The stable second broadband light beam is processed by the spatio-temporal wave packet unit and has a constant propagation speed and is not affected by dispersion in media with different refractive indices.

7. The spectral domain optical coherence tomography system with real-time feedback adjustment according to claim 6, characterized in that The electro - optical semi - transparent and semi - reflective mirror, the electro - optical semi - transparent and semi - reflective mirror driver, the deflection angle encoder, and the deflection angle encoder driver adjust the deflection angle of another part of the second broadband beam under the control of the control unit and transmit the sample reflected light with the same wavelength as another part of the second broadband beam to the spatio - temporal wave packet unit, the image beam unit, the interferometer, and the high - speed camera. Real - time feedback adjustment of the deflection angle of the second broadband beam can continuously select a monochromatic light, achieving an imaging resolution consistent with the spectral resolution of the light source.

8. The spectral domain optical coherence tomography system with real-time feedback adjustment according to claim 7, wherein The image beam unit includes an electro - optical semi - transparent and semi - reflective mirror, a collimating and beam - expanding device, a third grating, and a focusing lens connected in sequence through a fiber optic transmission unit; The electro - optical semi - transparent and semi - reflective mirror combines the optical path of the high - speed camera into the main optical path and transmits the sample reflected light with the same wavelength as a part of the second broadband beam reflected by the sample to the interferometer and the high - speed camera; The collimating and beam - expanding device is used to expand the diameter of a part of the second broadband beam and collimate a part of the second broadband beam; The third grating is a diffraction grating, which is used to reduce the influence of sample scattering on the imaging of the image beam unit; The focusing lens is a scanning lens, which is arranged in the output optical path of the image beam unit imaging and is used to focus a part of the second broadband beam whose position has been adjusted by the laser galvanometer scanning unit on the sample.

9. The spectral domain optical coherence tomography system with real-time feedback adjustment according to claim 8, characterized in that, The reference beam unit includes a field stop, a lens, and a reference mirror connected in sequence through a fiber optic transmission unit; The field stop is a field of view stop, which is used to obtain a circular light spot in the first reference beam; The lens is a cylindrical lens, which is used to transmit the first reference beam adjusted by the field stop; The reference mirror is a multi - prism reflector, which guides the first reference beam to the reference mirror and has a second reference beam orthogonal to the wavelength of the reference mirror returning to the interferometer.

10. The spectral domain optical coherence tomography system with real-time feedback adjustment according to claim 9, characterized in that, The optical paths of the three - dimensional laser galvanometer scanning unit, the image beam unit, and the high - speed camera are coaxial, and the sample is simultaneously within the scanning range of the three - dimensional laser galvanometer scanning unit, the imaging range of the image beam unit, and the shooting range of the high - speed camera; The focusing lens is fixed directly above the sample vertically and is used to focus the second broadband beam on the sample. At the same time, it serves as the imaging lens of the image beam unit, the scanning lens of the three - dimensional laser galvanometer scanning unit, and the shooting lens of the high - speed camera.

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